Commands using tr (349)

  • Join lines

    Even shorter. Stolen from comment posted by eightmillion.


    7
    tr "\n" " " < file
    randy909 · 2010-12-08 16:13:54 4
  • Look for English words in /dev/urandom

    Little faster alternative.


    7
    head -100000 /dev/urandom | strings|tr '[A-Z]' '[a-z]'|sort >temp.txt && wget -q http://www.mavi1.org/web_security/wordlists/webster-dictionary.txt -O-|tr '[A-Z]' '[a-z]'|sort >temp2.txt&&comm -12 temp.txt temp2.txt
    marssi · 2010-12-26 11:04:42 6
  • Terminal Keyboard Shortcut list

    This command will give you a list of available keyboard shortcuts according to stty. Show Sample Output


    7
    echo -e "Terminal shortcut keys\n" && sed -e 's/\^/Ctrl+/g;s/M-/Shift+/g' <(stty -a 2>&1| sed -e 's/;/\n/g' | grep "\^" | tr -d ' ')
    cicatriz · 2011-02-10 17:38:05 5
  • simulated text generator

    Show Sample Output


    7
    tr -dc a-z0-9 </dev/urandom | tr 0-8 \ | tr 9 \\n | sed 's/^[ \t]*//' | fmt -u
    rubenmoran · 2011-02-19 10:29:17 12
  • generate a randome 10 character password


    7
    tr -dc A-Za-z0-9_ < /dev/urandom | head -c 10 | xargs
    nottings · 2012-10-17 14:04:14 9
  • Transforms a file to all uppercase.

    Transforms a file to all uppercase.


    6
    tr '[:lower:]' '[:upper:]' <"$1"
    opexxx · 2009-10-08 11:34:07 3
  • Print a row of characters across the terminal

    Print a row of characters across the terminal. Uses tput to establish the current terminal width, and generates a line of characters just long enough to cross it. In the example '#' is used. It's possible to use a repeating sequence by dividing the columns by the number of characters in the sequence like this: seq -s'~-' 0 $(( $(tput cols) /2 )) | tr -d '[:digit:]' or seq -s'-~?' 0 $(( $(tput cols) /3 )) | tr -d '[:digit:]' You will lose chararacters at the end if the length isn't cleanly divisible. Show Sample Output


    6
    seq -s'#' 0 $(tput cols) | tr -d '[:digit:]'
    jgc · 2010-04-01 09:06:44 5
  • Generate a random left-hand password

    Generates a random 8-character password that can be typed using only the left hand on a QWERTY keyboard. Useful to avoid taking your hand off of the mouse, especially if your username is left-handed. Change the 8 to your length of choice, add or remove characters from the list based on your preferences or kezboard layout, etc.


    6
    </dev/urandom tr -dc '12345!@#$%qwertQWERTasdfgASDFGzxcvbZXCVB' | head -c8; echo ""
    TexasDex · 2010-06-17 19:30:36 3
  • Generate list of words and their frequencies in a text file.


    6
    tr A-Z a-z | tr -cs a-z '\n' | sort | uniq -c
    putnamhill · 2010-10-19 22:49:13 7
  • Create executable, automountable filesystem in a file, with password!

    This is just a proof of concept: A FILE WHICH CAN AUTOMOUNT ITSELF through a SIMPLY ENCODED script. It takes advantage of the OFFSET option of mount, and uses it as a password (see that 9191? just change it to something similar, around 9k). It works fine, mounts, gets modified, updated, and can be moved by just copying it. USAGE: SEE SAMPLE OUTPUT The file is composed of three parts: a) The legible script (about 242 bytes) b) A random text fill to reach the OFFSET size (equals PASSWORD minus 242) c) The actual filesystem Logically, (a)+(b) = PASSWORD, that means OFFSET, and mount uses that option. PLEASE NOTE: THIS IS NOT AN ENCRYPTED FILESYSTEM. To improve it, it can be mounted with a better encryption script and used with encfs or cryptfs. The idea was just to test the concept... with one line :) It applies the original idea of http://www.commandlinefu.com/commands/view/7382/command-for-john-cons for encrypting the file. The embedded bash script can be grown, of course, and the offset recalculation goes fine. I have my own version with bash --init-file to startup a bashrc with a well-defined environment, aliases, variables. Show Sample Output


    6
    dd if=/dev/zero of=T bs=1024 count=10240;mkfs.ext3 -q T;E=$(echo 'read O;mount -o loop,offset=$O F /mnt;'|base64|tr -d '\n');echo "E=\$(echo $E|base64 -d);eval \$E;exit;">F;cat <(dd if=/dev/zero bs=$(echo 9191-$(stat -c%s F)|bc) count=1) <(cat T;rm T)>>F
    rodolfoap · 2013-01-31 01:38:30 13
  • drop first column of output by piping to this


    6
    tr -s ' ' | cut -d' ' -f2-
    sesom42 · 2015-05-08 12:47:09 10
  • draw honeycomb

    tput setaf 1 && tput rev && seq -ws "___|" 81|fold -69|tr "0-9" "_" && tput sgr0 # (brick wall)


    6
    seq -ws "\\__/" 99|fold -69|tr "0-9" " "
    knoppix5 · 2018-11-13 06:39:37 262
  • Print with tabular


    6
    head -4 /etc/passwd | tr : , | sed -e 's/^/| /' -e 's/,/,| /g' -e 's/$/,|/' | column -t -s,
    wuseman1 · 2022-04-22 03:03:15 1014
  • List your largest installed packages.

    Calculates the size on disk for each package installed on the filesystem (or removed but not purged). This is missing the | sort -rn which would put the biggest packges on top. That was purposely left out as the command is slightly on the slow side Also you may need to run this as root as some files can only be checked by du if you can read them ;) Show Sample Output


    5
    dpkg --get-selections | cut -f1 | while read pkg; do dpkg -L $pkg | xargs -I'{}' bash -c 'if [ ! -d "{}" ]; then echo "{}"; fi' | tr '\n' '\000' | du -c --files0-from - | tail -1 | sed "s/total/$pkg/"; done
    pykler · 2009-10-12 14:57:54 5
  • Plot frequency distribution of words from files on a terminal.

    Uses the dumb terminal option in gnuplot to plot a graph of frequencies. In this case, we are looking at a frequency analysis of words in all of the .c files. Show Sample Output


    5
    cat *.c | { printf "se te du\nplot '-' t '' w dots\n"; tr '[[:upper:]]' '[[:lower:]]' | tr -s [[:punct:][:space:]] '\n' | sort | uniq -c | sort -nr | head -n 100 | awk '{print $1}END{print "e"}'; } | gnuplot
    taliver · 2009-11-20 14:53:26 7
  • Another Matrix Style Implementation

    A bit different from some of the other submissions. Has bold and uses all c printable characters. Change the bs=value to speed up and increase the sizes of the bold and non-bold strings.


    5
    echo -ne "\e[32m" ; while true ; do echo -ne "\e[$(($RANDOM % 2 + 1))m" ; tr -c "[:print:]" " " < /dev/urandom | dd count=1 bs=50 2> /dev/null ; done
    psykotron · 2009-12-19 19:05:04 4
  • Print a row of 50 hyphens

    Get there by going backwards and forgetting the numbers.


    5
    seq -s" " -50 -1 | tr -dc -
    DoNotRememberMe · 2010-03-25 06:00:24 32
  • Prepare a commandlinefu command.

    This command will format your alias or function to a single line, trimming duplicate white space and newlines and inserting delimiter semi-colons, so it continues to work on a single line. Show Sample Output


    5
    goclf() { type "$1" | sed '1d' | tr -d "\n" | tr -s '[:space:]'; echo }
    meathive · 2010-06-26 21:44:17 17
  • Get all shellcode on binary file from objdump

    Tired copy paste to get opcode from objdump huh ? Get more @ http://gunslingerc0de.wordpress.com Show Sample Output


    5
    objdump -d ./PROGRAM|grep '[0-9a-f]:'|grep -v 'file'|cut -f2 -d:|cut -f1-6 -d' '|tr -s ' '|tr '\t' ' '|sed 's/ $//g'|sed 's/ /\\x/g'|paste -d '' -s |sed 's/^/"/'|sed 's/$/"/g'
    gunslinger_ · 2010-07-11 15:44:48 112
  • Get a BOFH excuse

    Gets a BOFH excuse from the BOFH excuse server (towel.blinkenlights.nl port 666), and passes it through sed and tr to get rid of telnet connection stuff. Show Sample Output


    5
    telnet towel.blinkenlights.nl 666 | sed "s/=== The BOFH Excuse Server ===//" | tr -d '\n' && echo
    hintss · 2011-03-31 05:50:57 3
  • generate random tone


    5
    paste <(seq 7 | shuf | tr 1-7 A-G) <(seq 7 | shuf) | while read i j; do play -qn synth 1 pluck $i synth 1 pluck mix $2; done
    kev · 2012-04-09 15:22:19 3
  • Convert a script to one-liner

    Opposite: Convert an one-liner to script: foo() { <one-liner> ; } ... typeset -f foo ... unset -f foo


    5
    (sed 's/#.*//g'|sed '/^ *$/d'|tr '\n' ';'|xargs echo) < script.sh
    knoppix5 · 2013-10-26 23:23:51 16
  • Check if your desired password is already available in haveibeenpwnd database. This command uses the API provided by HIBP


    5
    function hibp() { sha1=$(echo -n "$1"|sha1sum|awk '{print toupper($0)}'|tr -d '\n'); curl -s -H $'Referer: https://haveibeenpwned.com/' https://api.pwnedpasswords.com/range/$(echo -n $sha1|cut -c1-5)|grep -i $(echo -n $sha1|cut -c6-40); }
    zmonkey · 2018-08-14 07:41:55 312
  • draw honeycomb

    Fill the entire terminal screen. Is COLUMNS or LINES are undefined run "resize"


    5
    yes "\\__/ " | tr "\n" " " | fold -$((($COLUMNS-3)/6*6+3)) | head -$LINES
    tomhol · 2018-11-23 08:21:55 379
  • Printable random characters

    Reads psuedorandom bytes from /dev/urandom, filtering out non-printable ones. Other character classes can be used, such as [:alpha:], [:digit:] and [:alnum:]. To get a string of 10 lowercase letters: tr -dc '[:lower:]' < /dev/urandom | head -c 10


    4
    tr -dc '[:print:]' < /dev/urandom
    gracenotes · 2009-02-05 21:51:14 18
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batch convert Nikon RAW (nef) images to JPG
converts RAW files from a Nikon DSLR to jpg for easy viewing etc. requires ufraw package

Change user within ssh session retaining the current MIT cookie for X-forwarding
When you remotely log in like "ssh -X userA:host" and become a different user with "su UserB", X-forwarding will not work anymore since /home/UserB/.Xauthority does not exist. This will use UserA's information stored in .Xauthority for UserB to enable X-forwarding. Watch http://prefetch.net/blog/index.php/2008/04/05/respect-my-xauthority/ for details.

Open Remote Desktop (RDP) from command line and connect local resources
The above command will open a Remote Desktop connection from command line, authenticate using default username and password (great for virtual machines; in the exampe above it's administrator:password), create a shared folder between your machine and the other machine and configure resolution to best fit your desktop (I don't like full screen because it make the desktop panels to disappear). The command will run in the background, and expect to receive parameters. You should enter hostname or IP address as a parameter to the command, and can also override the defaults parameters with your own.

High resolution video screen recording
$ gorecord foo.mp4 I've tried all of the screen recorders available for Linux and this is easily the best. xvidcap segfaults; VNC is too much hassle. There are alternatives of this command already here that I am just too lazy to reply to. Messing with the frames per second option, -r, 25 seems to be the best. Any lower and the video will look like a flipbook, if it records at all - -r 10 won't - any faster is the same, oddly enough. Edit: CLF doesn't like my long command to add audio, so here it is in the description. $ goaddaudio() ${ $if [ $# != 3 ]; then $ echo 'goaddaudio < audio > < src video > < dst video >' $ return $ fi $ $ f=goaddaudio$RANDOM $ ffmpeg -i "$2" &> $f $ d=$( grep Duration $f | awk '{print $2}' | tr -d ',' ) && $ rm $f && $ ffmpeg -i "$1" -i "$2" -r 25 -ab 192k -ar 44100 -sameq -t $d "$3" $}

Remove job from crontab by commandline
The "-u USER" is optional if root user is used

Do quick arithmetic on numbers from STDIN with any formatting using a perl one liner.
Good for summing the numbers embedded in text - a food journal entry for example with calories listed per food where you want the total calories. Use this to monitor and keep a total on anything that ouputs numbers.

Create the oauth token required for a Twitter stream feed
This is the THIRD in a set of five commands. See my other commands for the previous two. This step creates the oauth 1.0 token as explained in http://oauth.net/core/1.0/ The token is required for a Twitter filtered stream feed (and almost all Twitter API calls) This token is simply an encrypted version of your base string. The encryption key used is your hmac. The last part of the command scans the Base64 token string for '+', '/', and '=' characters and converts them to percentage-hex escape codes. (URI-escapeing). This is also a good example of where the $() syntax of Bash command substitution fails, while the backtick form ` works - the right parenthesis in the case statement causes a syntax error if you try to use the $() syntax here. See my previous two commands step1 and step2 to see how the base string variable $b and hmac variable $hmac are generated.

count how many times a string appears in a (source code) tree
grep -o puts each occurrence in a separate line

Mount directories in different locations
Like symlinked directories, you can mount a directory at a different location. For example mounting a directory from one location in to the http root without having to make your program follow symlinks or change permissions when reading.

Lookup hostname for IP address

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